Washington’s Legislative Ethics Board has launched an investigation into lobbyist-paid meals for lawmakers.

The inquiry follows our reporting with the Associated Press on lawmakers who dine out the most with lobbyists. The investigation was triggered by a formal citizen complaint filed last month – a complaint that’s just now coming to light.

It alleges five Republican state senators violated Washington’s ethics law by eating out regularly at lobbyist expense. They were the top five on our list of frequent diners.

Washington’s ethics law says lawmakers may accept free meals on an “infrequent basis.” But what does infrequent actually mean? It’s never been clearly defined.

The Legislative Ethics Board will consider the complaint at its September meeting. Lawmakers who violate the ethics law can face fines. The Board can also dismiss a case for lack of reasonable cause.

There’s another option too: the Board could use this complaint to issue clearer guidance to Washington lawmakers on what exactly constitutes meals on an “infrequent basis.”